Expose embed events for visualization fullscreen in the Preset Embedded SDK

What is the problem or goal the end user is trying to solve or accomplish?

When dashboards are embedded, users may open individual charts in “fullscreen” mode. This fullscreen is implemented as a modal overlay inside the Superset iframe. The host application cannot detect when this happens, so custom headers or layout logic on the host side overlap the fullscreen content. Customers want to adapt their layout (e.g., hide their own header, remove negative margins) automatically when a chart enters fullscreen, and restore it when the chart exits.

How are they solving it currently?

Some try to listen for the browser’s fullscreenchange event, but it doesn’t fire since Superset’s fullscreen is a modal inside the iframe, not true browser fullscreen.

No reliable or scalable solution exists with the current SDK.

What is the recommended solution by the Customer?

Enhance the Preset Embedded SDK so that it emits clear events (via callbacks or window.postMessage) for viz_fullscreen_enter and viz_fullscreen_exit. The host page could then subscribe and dynamically adjust its UI when embedded content switches in and out of fullscreen mode.